Nematoda

Introduction

Nemtodes are probably the most abundant group within the meiofauna. Their total species diversity may well exceed that of the insects (Platt et al. 1984). They are ubiquitous in the benthic marine environment, found in the vast majority of micro-habitats, from the supralittoral down to the abyssal depths. There are currently 326 species recorded for Chile (Lee et al. 2008), the majority intertidal. Most of these species were described by Wolfgang Weiser (1953, 1954, 1956, 1959) working with material collected during the Lund Expedition to Chile (1948-49) (Brattström and Dahl 1951). More recent information comes from the work on the family Epsilonematidae by Lorenzen (1974) and Clasing (1980, 1983, 1986), the work of Chen and Vincx (1998, 1999, 2000a, 2000b) in the Magallanes region, and reports on the nematofauna of the Atacama Trench (Gambi et al. 2003)

Morphology

Figure 1. A generalised nematode.

Figure 2. Amphids.

Figure 3. The different types of cuticle ornamentation.

Figure 4. Tail morphology.

Reproduction

Figure 5. Gential structure.

Figure 6. Gonads.

Feeding

Figure 7. Buccal structure.

Habitat

Table 1. Abundance and diversity associated with different habitats.

Spatial Variation

Temporal Variation

Table 2. Life-cycle data for different species.

Taxonomy

Table 3. Nematode classification.

Chilean Species List

Current list of the free-living marine nematode species to be found in Chilean waters, ordered by Family.

References

Brattström, H. and Dahl, H. (1951) General account, lists of stations, hydrography. Reports of the Lund University Chile expedition 1948-49, 1. C.W.K. Gleerup, Lund, Sweden. 39 pp.

Chen, G. and Vincx, M. (1998) Nematodes from the Strait of Magellan and the Beagle Channel (Chile): description of four new species of the Comesomatidae. Hydrobiologia379: 97-118.

Chen, G. and Vincx, M. (1999) Nematodes from the Strait of Magellan and the Beagle Channel (Chile): the genus Sabatieria (Comesomatidae: Nematoda) with the description of Sabatieria coomansi n. sp. Hydrobiologia 405: 95-116.

Chen, G. and Vincx, M. (2000a) Nematodes from the Strait of Magellan and the Beagle Channel (Chile): the genera Cervonema and Laimella (Comesomatidae: Nematoda).Hydrobiologia 427: 27-49.

Chen, G. and Vincx, M. (2000b) New and little known Nematodes (Monhysteroida, Nematoda) from the Strait of Magellan and the Beagle Channel (Chile). Hydrobiologia429: 9-23.

Clasing, E. (1980) Postembryonic development in species of Desmodoridae, Epsilonematidae and Draconematidae. Zoologiche Anzeiger 204: 337-344.

Clasing, E. (1983) Leptepsilonema gen.n. (Nematoda, Epsilonematidae) from Chile and the Caribbean Sea. Zoologica Scripta 12: 13-17.

Clasing, E. (1986) Epsilonematidae (Nematoda) from Chiloe (southern Chile) with descriptions of two new species. Zoologica Scripta 15: 295-303.

Gambi, C., Vanrusel, A. and Danovaro, R. (2003) Biodiversity of nematode assemblages from deep-sea sediments of the Atacama Slope and Trench (South Pacific Ocean). Deep Sea Research I 50: 103-117.

Lee, M.R., Clarke, M., Fernandez, M.E., Gonzalez, C., Rozbaczylo, N., Valdovinos, C., Hermosilla, C., Prado, L. and Castilla, J.C. (2008) Diversity of free-living benthic marine invertebrates in Chile. Revista Chilena Historia Natural 81: 51-67.

Lorenzen, S., 1974. Glochinema nov. gen. (Nematodes, Epsilonematidae) aus Südchile.Mikrofauna des Meeresbodens 47: 393–410.

Platt, H.M., Shaw, K.M. and Lambshead, P.J.D. (1984) Nematode species abundance patterns and their use in the detection of environmental perturbations. Hydrobiologia118: 59-66.

Wieser, W. (1953) Free-living marine nematodes. I. Enoploidea. Reports of the Lund University Chile Expedition 1948-1949. 10. C.W.K. Gleerup, Lund. 155pp.

Wieser, W. (1954) Free-living marine nematodes. II. Chromadoroidea. Reports of the Lund University Chile Expedition 1948-1949. 17. C.W.K. Gleerup, Lund. 148pp.

Weiser, W. (1956) Free-living marine nematodes. III. Axonolaimoidea and Monhysteroidea. Reports of the Lund University Chile Expedition 1948-1949. 26. C.W.K. Gleerup, Lund. 115pp.

Weiser, W. (1959) Free-living marine nematodes. IV. General part. Reports of the Lund University Chile Wxpedition 1948-1949. 34. C.W.K. Gleerup, Lund. 111pp.